This invention relates to the field of surface mountable wire connector blocks formed for holding a plurality of wire connectors, and, more particularly, to methods for establishing connections with the wire connectors.
Wire connector blocks are known in the prior art which are formed to be mounted to an opening in a mounting surface, such as a panel, to fixedly support a plurality of wire connectors relative to the mounting surface. The wire connectors are used to define electrical connections between wires located on both sides of the panel. Typically, the wire connectors are insulation displacement connectors (IDC""s). IDC""s are formed to grippingly engage wire conductors inserted thereinto, thereby forming electrical connections between the electrical conductors and the IDC""s. Where used with a panel-mounted wire connector block, the IDC""s are disposed to grippingly engage wire conductors located in front of the panel, and have terminal strips which protrude from the rear of the panel. In turn, wires are connected to the terminal strips typically in one of two ways.
First, individual wires may be wrapped about the terminal strips in a procedure aptly named xe2x80x9cwire wrappingxe2x80x9d. The wires are wrapped helically about the terminal strips to define contiguous loops, with often ten loops being formed to ensure an acceptable electrical connection is defined. To ensure continued integrity of the connections, liquid potting material is poured about the terminal strips and the wrapped wires, and solidified. The potting material-application process is facilitated by a wall extending rearwardly of the wire connector block, which encircles all of the protruding terminal strips, and acts as a mold for the potting material. As is readily appreciated, the terminal strips must be formed with sufficient length to accommodate all of the wound loops. Commonly, the terminal strips are formed with a length of 0.375xe2x80x3 to provide sufficient length about which a wire can be wrapped. Also, the rearwardly-extending wall is typically formed to extend coextensively with, and even beyond, the terminal strips to ensure sufficient volume is defined to encompass the terminal strips and wrapped wires with the potting material. With this embodiment, the resulting structure is a plurality of discrete wires extending from the solidified potting material.
Second, a printed wire board (PWB) may be mounted onto the terminal strips and fastened thereto using wave soldering. Wires are then connected to the PWB and extended therefrom to other locations. Since no wires need be wrapped about the terminal strips, the terminal strips are formed shorter than where wire wrapping is used, and typically with a length 0.125xe2x80x3. Additionally, the wire connector block is not formed with a rearwardly-extending wall, since no potting material is used.
Due to the use of two different methods for mounting wire to wire connectors, wire connectors have been formed with terminal strips of two different lengths. Additionally, two different wire connector block designs have been developed in the prior art: those having and those not having a wall that extends rearwardly sufficiently to define an appropriate mold for potting material. However, it is undesired to maintain two inventories of wire connectors and, separately, two inventories of wire connector blocks.
To overcome shortcomings in the prior art, a wire connector block is provided which is formed to mount onto a mounting surface (e.g. a panel), and which is formed with a rearwardly extending wall. A tab extends from the wall which provides a surface for engaging a PWB. Wire. connectors are used with the wire connector block having lengths greater than the wall, so as to extend therebeyond. It is preferred that IDC""s be used having terminal strips which extend beyond the rearwardly-extending wall. In this manner, wire wrapping can be used to connect wires about portions of the terminal strips recessed below the wall, and, alternatively, portions of the terminal strips extending beyond the wall can be wave soldered to a PWB. The wall acts as a mold for potting material where wire wrapping is used. Other wire connectors known to those skilled in the art that are usable with mounted wire connector blocks may be used with the subject invention.
Additionally, a method is provided for mounting wires to a PWB secured to the wire connectors. In particular, a ribbon wire is connected to the PWB using any technique known by those skilled in the art, including soldering, and the use of a releasable connector. The ribbon wire is bent to extend at least partly across and in proximity to the PWB so as to define an enclosed space therebetween. A substance, such as silicon gel, may be injected into the enclosed space to shield the terminal strips and the PWB from external environmental effects.
It is preferred than the ribbon wire be connected to the top surface of the PWB (i.e., the surface of the PWB facing the wire connector block). As such, the ribbon wire must be bent around the edge of the PWB to be able to extend across and in proximity to the PWB, and, the bending of the ribbon wire provides strain relief thereto.
As an additional feature, a wire guide preferably extends from the wire connector that includes a slot extending therethrough shaped to accommodate the passage of the wire ribbon. The wire guide is located adjacent to the mounted PWB, and preferably opposite to the point(s) of connection of the ribbon wire with the PWB, so as to receive the wire ribbon after extending across the PWB. The wire guide provides stability to the assembly and limits movement of the wire ribbon relative to the PWB. Additionally, it is preferred that a channel be formed in the wire guide extending from the peripheral edge into communication with the slot. Advantageously, the ribbon wire can be passed laterally through the channel and into the slot, thereby avoiding the necessity of threading the entire ribbon wire through the slot.
The method of the subject invention forms an assembly of wire connectors, a PWB, a wire ribbon, and, silicon gel, that results in a stable collection of wire connections and wires that are easy to manage.
Other objects and features of the present invention will become apparent from the following detailed description, considered in conjunction with the accompanying drawing figures. It is to be understood, however, that the drawings, which are not to scale, are designed solely for the purpose of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims.